Fencing

ABSTRACT

A fencing for preventing insects to enter an open air area comprising a substantially upright structure with a height suitable to prevent low flying insects to enter said open air area. The structure of the fencing is impregnated with an insecticide.

FIELD OF THE INVENTION

The present invention relates to a fencing for preventing insects toenter an area. The invention also relates to use of such a fencing.

BACKGROUND OF THE INVENTION

In order to protect human beings and animals from diseases and annoyingeffects of nuisance insects, as for example bites or stings, a number ofsolutions have been developed throughout the years. One of the mostlyknown solutions is covering a certain area, for example the bed of ahuman being, by a mosquito net that prevents the person under themosquito net from being bit by insects as mosquitoes or flies.

In U.S. Pat. No. 5,048,551, a special development within the field ofprotection of human beings against flying insects is disclosed, namely afloating insect screen for a user in a swimming pool. This insect screenhas a base member connected to a number of upright members between whicha mesh materials is attached preventing insects to reach the personunder the floating insect screen.

In order to increase the efficiency of mosquito nets, it is known toimpregnate the mesh material of the net with an insect repellent or evenwith insecticides to kill insects that touch the net structure. Forpeople wearing clothes, also garments may be impregnated with insectrepellents and/or insecticides as a protective agent.

Different agents to be used as insect repellents and insecticides aredisclosed in international patent applications WO 98/18998 and WO01/37662 and in European patent application EP 382 382 and referencestherein. Also disclosed in these patent applications and in referencestherein are water repellent agents, for example silicon oil or wax, toprevent washing off the insect repellent or insecticide and alsoUV-radiation protecting agents that prevent the insect repellent orinsecticide from being decomposed due to UV-radiation.

Another attempt to reduce nuisance by insects is through killing ofinsects by air spraying, for example in insect breeding places. Airspraying of insecticides is furthermore used to reduce the effect ofinsects on agricultural fields.

Especially in tropical countries, a large number of insects, typicallyflying insects, causes substantial problems as vectors and transmittersof infectious diseases, as for example trypanosomiasis, affecting humanbeings and animals, why tremendous efforts have been concentrated incontrolling these insects. However, especially for poorer countries, theexpenses related to these efforts, especially the high price ofinsecticides, has a non-negligible influence on the economy of thesecountries. Using large amounts of insecticides by spraying over, forexample agricultural fields, also may cause environmental problems.Further, it limits the possibilities for these countries to export theircrops, since pesticide residues may be left on the crop and be detectedby the authorities in importing countries. The European or NorthAmerican farmer is confronted with the same problem of protecting versusretention of crop after spraying. When applying pesticides directly oncrops, retention times must be respected, but this may be hard forfarmers, especially when harvesting sorts of fruits and vegetables thatare harvested over a period. By respecting retention time for ripeningfruits, younger fruits risk to be damaged to a point that they can neverbe sold. In addition it implies the risk of resistance of the insectsagainst the insecticide.

Regarding the fact that a large number of flying insects are a nuisanceto human beings and animals either directly through insect attack orindirectly through agricultural effects caused by insects, it would bedesirable to find a solution how to limit the negative influence ofinsects on daily life. Particularly, it would be desirable to find asolution to repel or kill insects that attempt to reach humans, animalsor agricultural plants. Especially, it is interesting to prevent acontact between the insect and the host (human, animal or plant), sinceeven a short contact time may be enough for the insect to damage thehost. Insects carrying diseases may need only a few seconds afterlanding to damage the host. Treatment of walls in a house may thus wellkill the mosquitoes, but the mosquitoes mostly rest on the walls afterbiting and have as such already transferred a disease. Aphidstransferring opportunistic virus probe plants at landing and in this waytransfer the virus. Both group of insects will land on a net thatprotects the host and even they may physically penetrate, they willalready have received a dosage of insecticide that may disturb theirbehaviour and thus decrease their chance to transfer a disease.

DESCRIPTION/SUMMARY OF THE INVENTION

This object is achieved by a method for preventing low-flying insects toenter an open air area. Depending on the wherein the method comprisesproviding a fencing with a substantially upright structure at leastpartly surrounding the area, the structure having a height suitable toprevent low-flying insects to enter the open-air area, preferably aheight of between 0.5 m and 2 m, wherein at least part of the structureis provided with an insecticide transferable to insects touching the atleast part of the structure.

In order to understand and appreciate the functioning of this fencing,the following observations are essential. As intensive studies haverevealed, the majority of flying nuisance insects, as for instance thetsetse fly, stomoxys or tabanids, are flying at a relatively low height,typically half a meter above ground. Thus, surrounding an open air area,for example an agricultural field or a children play ground, with afencing, for example with a height of 1.5 meters, may prevent the lowflying insects from reaching the open air area. This appealingly simplesolution to a problem that has existed for thousands of years could onlybe found having knowledge of the behaviour of such nuisance insects.

The choice of the height of the fence, for example 1 m, 1.5 m or 2 m,may also take into consideration the presence of pollinating insectslike honey bees that often have a higher flying height than pestinsects. An optimal height thus considers as well target insects asnon-target insects.

Insects meeting the fence in their normal flying height will often landon the net before flying on to the target or crawl through the holes. Inorder to prevent pest or nuisance insects after having touched the fencestructure to fly to their target, at least part of the structure of afencing according to the invention comprises an insecticide transferableto insects touching this part of a structure. In case, that thestructure is a rigid wall or a sheet like a tarpaulin, the insecticidemay be applied as a surface layer, or it may even be incorporated intothe wall structure.

The advantage of a fencing according to the invention as compared tomosquito nets is that it is unnecessary to cover the area in order toprevent insects from entering. Even large areas as agricultural fieldsor villages may be surrounded by a fencing according to the inventionrequiring only relatively small amounts of material as compared to acomplete covering of the area.

A fencing with an insecticide has the further advantage that insectsalready inside the area may reach and touch the fencing and receiveinsecticide which will reduce the density of insects in the areasurrounded by the fencing.

In order to prevent insects that are crawling on the ground or boringthrough the soil, for example tipulid or scarabid larvae, from enteringthe area to be protected, the structure of the fencing may comprise aground part which extends into the ground. This ground part may extendinto the ground from a general structure of the fencing, but preferablyit extends from a mesh into the ground. By extending into a certaindepth into the ground, this ground part also prevents insects that aretraversing the top soil from entering the area to be protected.

Typically however, it is not necessary that the fencing for use for sucha method reaches the ground. This also implies an easier and cheapermounting of the fencing. Therefore, preferably, the lower edge of thefencing is positioned at a certain distance, for example 5 cm to 20 cm,above the ground allowing crawling insects to pass the fencing. In fact,in some cases, it is highly desirable that crawling insects transversethe fencing, because spiders and certain beetles like carabid andcarnivorous beetles are useful and desired inside the area. The insectcontrol with a fence thus includes environmental considerations betterthan a plant covering spray application.

In its most simple version, the fencing according to the invention neednot necessarily comprise an insecticide, though the use of such aninsecticide increases the efficiency. Thus, a fencing having asubstantially upright structure wherein the structure has a heightsuitable to prevent low flying insects to enter the open air area,preferably a height of between 0.5 m and 2 m, wherein the structure hasa lower edge positioned at a certain height above ground, preferablybetween 5 cm and 20 cm above ground, for allowing crawling insects topass the fencing and without an insecticide may as well serve the abovementioned purpose to a certain degree. In this case however, it ishighly preferable that the fencing comprises a top part which is bentinto a concave structure for trapping insects. Insects experiencing ablocking by the fencing on their flying path may try to fly up along thesurface of the fencing in order to pass the obstacle. However, whenreaching the bent top part, they will get trapped and finally die. Inthis case, use of insect attracting pheromones in the top part may be ofadvantage to increase the chance for trapping insects.

However, the highest benefit for a fencing according to the inventionhas been experienced by including an insecticide in at least part of thestructure, the insecticide being transferable to insects touching thisat least part of the structure.

An applicable insecticide may be based on pyrethroids, organophosphates,nicotinoids, neonicotinoids, pyridines, pyrimidin, pyrazoles, pyrrols,dialyl hydrazines, sulphonates, quinazolines, azomethines, trizines,benzoul-urea compounds, or carbamates. A number of possible agents arerefereed in international patent applications WO 98/18998 and WO01/37662 and in European patent application EP 382 382.

In a certain embodiment, such a fencing is a rigid, substantiallyupright structure of a certain height, for example one or two metres.The term substantially upright covers vertical fencing structures andstructures that are inclined, without however thereby achieving acomplete covering of the area. Thus, the area to be protected remains anopen air area, only with a protecting fencing along the edge of the openair area and not covering the area. The fencing may be a rigid wall, forexample made of wood, glass, metal or polymer.

Preferably however, such a fencing is achieved by rigid, substantiallyupright frame members, for example wooden poles, between which theprotective structure, for example a non-rigid structure, for example amesh, textile, or a foil is attached. As an alternative to a netstructure, a perforated foil or laminate may be used as well. A suitablemesh structure could be the same as the one used for mosquito nets,which for example are used for covering windows or doors in buildings asa protective means against insects. Such a mesh may then have openingswith a size that prevent the low flying insects from easily goingthrough the mesh. But, even with quite large holes as compared to theinsect, most insects will intercept the net and use it for a restingplace. When provided with an insecticide, the net may an effective tooleven in the case where insects easily may penetrate it.

A structure for a fencing according to the invention as a mesh, atextile, or a laminate may comprise man made fibres as well as naturalfibres, for example viscose, cotton, glass fibres, polymer fibres, forexample made of polyvinylchloride (PVC), polyester, polyethylene,polystyrene, polyoxyethylenes, polypropylene, polyamides or nylon, andmixtures or copolymers including these materials.

The material of the structure may be impregnated or surface treated withan insecticide or the insecticide may be incorporated into the materialof the structure. How such an impregnation or incorporation of theinsecticide may be achieved is generally described in prior art, forinstance for a polyester net in international patent application WO01/37662. It is an advantage, if the insecticide in the fencingstructure is comprised at least partly inside the structure andgradually migrates to the surface of the structure, such thatinsecticide transfer to insects touching the structure is possible foran appreciable time, preferably several years.

However, in certain special applications, a short lifetime of theinsecticide may be preferred. Especially, when, at a later stage, thestructure is removed and destroyed, it is desirable that the lifetime ofthe insecticide has been short.

In principle, a fencing according to invention could be arranged as afloating fencing on water, which would be usable to protect people oranimals in a water environment, for example a swimming pool or anoutdoor playground in the water at the beach. Preferably however, thefencing according to the invention is supported on solid grounds.

In case an insect flies into the structure of the fencing, for instancea mesh structure, the insect may try to fly along the structure of thefencing in an upwards direction for bypassing the obstacle. Taking thisfact into account, the structure in a further development has a top partcomprising an insecticide. The effect of this trapping part may beincreased by incorporating arrestant types of chairomones (chemical usedin insect communication), attractants or pheromones. This is yet anotherway to improve the selectivity of the fence between pest and non-pestinsects.

The top part may advantageously be bent for trapping those insects thatmove upwards along the surface of the structure. As an insect movesupwards along the structure, it will at some point be trapped in thebent part and touch this bent top part, whereby insecticide istransferred to the insect. In this case, it may be advantageous that aninsect attracting agent, for example pheromones or lures, is used in thebended part to improve the efficacy as a trap.

In the further embodiment, the top part may comprise an insecticidewhich is different from the rest of the structure. For example, insectsthat have become resistant to the insecticide of the mesh maynevertheless be killed in case that they touch the top part of thefencing. The combination of two insecticides in separate parts of thestructure may also be regarded as a mechanism to prevent or delay theonset of resistance to both insecticides when not already present.

As the fencing according to the invention is used in open air, it isimportant that the insecticide is not washed off the structure, andfurthermore the insecticide should be prevented from being degraded dueto UV-radiation. Both problems are dealt with for a polyester structurein international application WO 01/37662 and references therein suchthat also this problem is solved by combination of prior art knowledgewith the fencing according to the invention. Protection can be achievedwith a suitable covering of the surface, an impregnation with or anintegration of an insecticide migrating agent.

In fact, by using a fencing with a top part that bends, for example withan approximately circular bending, insects that touch the structure andthen fly upwards may be trapped in the top part and die therein. This isthe more efficient if an insect attracting agent, for example pheromonesand lures, are used in the bended part to improve the efficacy as atrap. In this case, a structure of a fencing to be efficient does noteven need an insecticide or. Thus in certain cases, for a number ofinsects, an open air area may be kept free from flying insects bysurrounding the open air area with a fencing that has a bent top part,where the top part acts as a trap.

Preferably the structure according to the invention is impregnated orcovered with an agent that protects against weathering and UV induceddecomposition. The insecticide may be incorporated into the structureand may be combined with chemicals or copolymers that regulate itsmigration, protect it against weathering and especially against UVlight. To improve the latter effect, some of these chemicals may migrateto the surface as the insecticide and thus reduce UV inactivation of theinsecticide already on the surface. The gradual migration to the surfaceof insecticide aims at rendering the protection effective for months,preferably years for the insecticides. In case that insect repellentsare advantageous in connection with the invention and incorporated inthe structure, these repellents may stay effective for months by thismethod.

Further, for insect that are attracted to pheromones like beetles andmoths, pheromone or lure chemical may be integrated as part of thestructure or coated to the surface as described above. Since the effectof repellent, lures and pheromones are based on evaporation of theactive material and therefore a more rapid release of active materialthan that of insecticides, which may work by contact only, the net orlaminate may be constructed in a way that the part embodying thesematerials are replaceable or may be retreated with intervals.

In still another development of the invention the structure of thefencing may be desired to be attracting to certain insects. Visiblecolours may act attracting on certain insects and be used as a colourfor the structure of the fencing. For example, yellow is attractive forcertain beetles, flies and aphids.

In case that the main intention is to kill insects, it may be ofadvantage that the structure of fencing according to the invention isblack, because black is invisible for a large number of insects. Thiskind of insects will be prevented from seeing the structure, forinstance the mesh, and fly directly into it, whereby insecticide istransferred to the insect, which then is killed.

A number of advantages are achieved by a fencing according to theinvention. Being used as a fencing surrounding cattle grassing units,stressing of the cattle due to insect bites is omitted as well aspotential diseases vectored by these insects to the animals. The resultis higher milk and meet production, the effect of which may be mostpronounced in tropical and subtropical regions. The reduction of diseasevectors generally improves the health situation in especially tropiccountries with reduced need for drugs, which also has a positive impacton the economy. But not only in tropic countries, a fencing according tothe invention is advantageous. Also in more temperate climatic zones,such a fencing finds application, for example in crop protection againstlow flying or ground crawling or hopping insects.

Disease that may be prevented by using a fencing according to theinvention include trypanosomiasis (sleeping sickness) as transferred bytsetse flies, a number of diseases transferred by ticks: east coastfever, cowdriosis, anaplasmosis, babesiosis, dermatophilosis(streptotrichosis), secondary skin infection, malaria, leishmaniasis,dengue, filariasis, elephantiasis and onchocerciasis and other forms oftrypanosomiasis, mastitis, and blow fly infections on sheep and cattle.Furthermore, prevented may be anaemia/haematocrit induced by stomoxys,tabanids, laekatoplajohs and PCV.

Table 1 lists a number of important mosquito born viral diseases ofhumans and corresponding known vectors, and table 2 lists a number ofhuman pathogens mechanically transmitted by houseflies and theirrelatives. These and further diseases may be prevented or at leastreduced for humans and animals surrounded at least in part by thefencing according to the invention.

TABLE 1 Geographic Virus Distribution Vectors Alphaviruses ChikungunyaAfrica, Asia Aedes aegypti, other Aedes species Eastern equine NorthAmerica, Culiseta melanura, Aedes encephalitis South Americataeniorhynchus, Aedes solli- citans O'nyong-nyong Africa Anophelesfunestus, Anophe- les gambiae, Mansonia spp Ross River Australia,Pacific Culex annulirostris, Aedes Islands vigilax, Aedes polynesiensis,Aedes aegypti Sindbis Africa, Asia, Culex univitatus, Culex tri-Australia, Europe taeniorhynchus Venezuelan equine North and South Culexmelanacom species, encephalitis America Psorophora confinnis Westernequine Noth and Sout Culex tarsalis, Aedes species encephalitis AmericaFlaviviruses Japanese encephalitis Asia, New Culex tritaeniorhynchusGuinea group, Culex annulirostris, Culex annulus Murray ValleyAustralia, Culex annulirostris, Culex encephalitis New Guineabitaeniorhynchus Rocio South America Aedes scapularis St. Louisencephalitis North and South Culex pipiens complex, Amrica Culextarsalis, Culex nigripalpus, Culex restuans, Culex salinarius West NileAfrica, Asia, Culex univittatus, Culex Europe vishnui subgroup DengueTropicopolitan Aedes aegypti, Aedes albo- pictus, Aedes polynesiensis,Aedes hensilli, Aedes scutel- laris complex Yellow fever Africa Aedesaegypti, Aedes africa- nus, Aedes simpsoni, Aedes furcifer-tayloriAmericas Aedes aegypti, Hamagogus janthinomys, Haemagogus spegazzinit,Haemagogus leucocelaenus, Sabethes clilo- ropterus Zika Africa, AsiaAedes aegypti, Aedes africanus Bunyaviruses La Crosse North AmericaAedes triseriatus Tahyna Africa, Asia, Aedes vexans Europe OropoucheSouth America Culex species Phleboviruses Rift Valley Fever Africa Culexpipiens complex, Aedes species

TABLE 2 Agent Classification Source Virus Poliomyelitis FeecesCoxsackievirus Feeces hapatitis A Feeces Enteroviruses Feeces ReckettsiaBacterium Coxiella burnetti Milk Chiamydia trachomatis ConjunctivaShigella species Feeces Salmonella species Feeces Salmonella typhiFeeces Escherichia coli Feeces Vibrio cholerae Feeces Helicobactor pylonFeeces Bacterial conjunctivitis Conjunctiva Spirochete Treponemaperlenue Skin ulcers Protozoon Entamoeba histolytica Feeces Cestode(eggs) Taenia solium Feeces Dipylidium caninum Feeces Diphyllobothniumlatum Feeces Nematode (eggs) Ascaris lumbnicoides Feeces Trichunistrichiura Feeces Enterobius vermiscularis Feeces

The present invention relates to but is not limited to the followingactive insecticides selected from the group comprising pyrethroidcompounds such as

-   -   Ethofenprox: 2-(4-ethoxyphenyl)-2-methylpropyl-3-phenoxybenzyl        ether,    -   Fenvalerate: (RS)-alpha-cyano-3-phenoxybenzyl        (RS)-2-(4-chlorophenyl)-3methylbutyrate,    -   Esfenvalerate:        (S)-alpha-cyano-3-phenoxybenzyl(S)-2-(4-chlorophenyl)-3-methylbutyrate,    -   Fenpropathrin: (RS)-alpha-cyano-3-phenoxybenzyl        2,2,3,3-tetramethylcyclopropanecarboxylate,    -   Cypermethrin: (RS)-alpha-cyano-3-phenoxybenzyl (1RS)-cis,        trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,    -   Permethrin: 3-phenoxybenzyl        (1RS)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,    -   Cyhalothrin:        (RS)-alpha-cyano-3-phenoxybenzyl(Z)-(1RS)-cis-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopro        panecarboxylate,    -   Deltamethrin: (S)-alpha-cyano-3-phenoxybenzyl        (1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate,    -   Cycloprothrin: (RS)-alpha-cyano-3-phenoxybenzyl        (RS)-2,2-dichloro-1-(4-ethoxyphenyl)cyclopropanecarboxylate,    -   Fluvalinate (alpha-cyano-3-phenoxybenzyl        N-(2-chloro-alpha,alpha,alpha-trifluoro-p-tolyl)-D-valinate),    -   Bifenthrin: (2-methylbiphenyl-3-ylmethyl)0(Z)-(1        RS)-cis-3-(2-chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethylcyclopropanecarboxylate,    -   2-methyl-2-(4-bromodifluoromethoxyphenyl)propyl    -   (3-phenoxybenzyl) ether,    -   Tralomethrin: (S)-alpha-cyano-3-phenoxybenzyl        (1R-cis)3((1RS)(1,2′,2′,2′-tetrabromoethyl))-2,2-dimethylcyclopropanecarboxylate,    -   Silafluofen: 4-ethoxyphenyl        (3-(4-fluoro-3-phenoxyphenyl)propyl}dimethylsilane,    -   D-fenothrin: 3-phenoxybenzyl (1R)-cis, trans)-chrysanthemate,    -   Cyphenothrin: (RS)-alpha-cyano-3-phenoxybenzyl (1R-cis,        trans)-chrysanthemate, D-resmethrin: 5-benzyl-3-furylmethyl        (1R-cis, trans)-chrysanthemate,    -   Acrinathrin: (S)-alpha-cyano-3-phenoxybenzyl        (1R-cis(Z))-(2,2-dimethyl-3-(oxo-3-(1,1,1,3,3,3-hexafluoropropyloxy)propenyl(cyclopropanecarboxylate,    -   Cyfluthrin: (RS)-alpha-cyano-4-fluoro-3-phenoxybenzyl        3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,    -   Tefluthrin: 2,3,5,6-tetrafluoro-4-methylbenzyl (1RS-cis        (Z))-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarbo        xylate,    -   Transfluthrin: 2,3,5,6-tetrafluorobenzyl        (1R-trans)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,    -   Tetramethrin: 3,4,5,6-tetrahydrophthalimidomethyl (1RS)-cis,        transchrysanthemate,    -   Allethrin: (RS)-3-allyl-2-methyl-4-oxocyclopent-2-enyl        (1RS)-cis, transchrysanthemate,    -   Prallethrin: (S)-2-methyl-4-oxo-3-(2-propynyl)cyclopent-2-enyl        (1R)-cis, transchrysanthemate,    -   Empenthrin: (RS)-1-ethynyl-2-methyl-2-pentenyl        (1R)-cis,trans-chrysanthemate,    -   Imiprothrin: 2,5-dioxo-3-(prop-2-ynyl)imidazolidin-1-ylmethyl        (1R)-cis,        trans-2,2-dimethyl-3-(2-methyl-1-propenyl)-cyclopropanecarboxylate,    -   D-flamethrin: 5-(2-propynyl)-furfuryl (1R)-cis,        trans-chrysanthemate, and 5-(2-propynyl)furfuryl        2,2,3,3-tetramethylcyclopropanecarboxylate;

The presently preferred pyrethroid includes deltamethrin, etofenprox,alfacypermethrin, lambdacyhalothrin, and cyfluthrin.

Other active insecticides that may be used alone or in combination, butpreferably not mixed with pyretrhoids, are e.g. carbamate compounds suchas

-   -   Alanycarb:        S-methyl-N[[N-methyl-N—[N-benzyl-N(2-ethoxy-carbonylethyl)        aminothio]carbamoyl]thioacetimidate,    -   Bendiocarb: 2,2-dimethyl-1,3-benzodioxol-4yl-methylcarbamate),    -   Carbaryl (1-naphthyl N-methylcarbamate,    -   Isoprocarb: 2-(1-methylethyl) phenyl methylcarbamate,    -   Carbosulfan: 2,3        dihydro-2,2-dimethyl-7-benzofuranyl[(dibutylamino)thio]methylcarbamate,    -   Fenoxycarb: Ethyl[2-(4-phenoxyphenoxy)ethyl]carbamate,    -   Indoxacarb:        Methyl-7-chloro-2,3,4a,5-tetrahydro-2-[methoxycarbonyl(-4-trifluoromethoxyphenyl)]    -   Propoxur: 2-isopropyloxyphenol methylcarbamate,    -   Pirimicarb:        2-dimethylamino-5,6-dimethyl-4-pyrimidinyl-dimethylcarbamate,        Thidiocarb: Dimethyl        N,N′(thiobis((methylimino)carbonoyloxy)bisethanimidiothioate),    -   Methomyl: S-methyl N-((methylcarbamoyl)oxy)thioacetamidate,    -   Ethiofencarb: 2-((ethylthio)methyl)phenyl methylcarbamate,    -   Fenothiocarb: S-(4-phenoxybutyl)-N,N-dimethyl thiocarbamate,    -   Cartap:        S,S′-(2-5dimethylamino)trimethylene)bis(thiocarbamate)hydrochloride,        Fenobucarb: 2-sec-butylphenylmethyl carbamate,        3,5-dimethylphenyl-methyl carbamate,    -   Xylylcarb: 3,4-dimethylphenylmethylcarbamate,

Additionally, active insecticides such as organophosphorous compoundsmay be applied in accordance with the invention including compounds suchas

-   -   Fenitrothion: O,O-dimethyl 0-(4-nitro-m-tolyl) phosphorothioate,    -   Diazinon: 0,0-diethyl-0-(2-isopropyl-6-methyl-4-pyrimidinyl)        phosphorothioate,    -   Pyridaphenthion: 0-(1,6-dihydro-6-oxo-1-phenylpyrazidin-3-yl)        0,0-diethyl phosphorothioate,    -   Pirimiphos-Etyl: 0,0-diethyl 0-(2-(diethylamino)        6-methyl-pyrimidinyl) phosphorothioate,    -   Pirimiphos-Methyl:        0-[2-(diethylamino)-6-methyl-4pyrimidinyl]0,0-dimethyl        phosphorothioate,    -   Etrimphos:        0-6-ethoxy-2-ethyl-pyrimidin-4-yl-0,0-dimethyl-phosphorothioate,    -   Fenthion: 0,0-dimethyl-0-[-3-methyl-4-(methylthio) phenyl        phosphorothioate,    -   Phoxim: 2-(diethoxyphosphinothoyloxyimino)-2-phenylacetonitrile,    -   Chlorpyrifos: 0,0-diethyl-0-(3,5,6-trichloro-2-pyrinyl)        phosphorothioate,    -   Chlorpyriphos-methyl: 0,0-dimethyl        0-(3,5,6-trichloro-2-pyridinyl) phosphorothioate,    -   Cyanophos: 0,0-dimethyl 0-(4cyanophenyl) phosphorothioate,    -   Pyraclofos:        (R,S)[4-chlorophenyl)-pyrazol-4-yl]-O-ethyl-S-n-propyl        phosphorothioate, Acephate: 0,S-dimethyl        acetylphosphoroamidothioate,    -   Azamethiphos:        S-(6-chloro-2,3-dihydro-oxo-1,3-oxazolo[4,5-b]pyridin-3-ylmethyl        phosphorothioate,    -   Malathion: 0,0-dimethyl phosphorodithioate ester of diethyl        mercaptosuccinate,    -   Temephos: (0,0′(thiodi-4-1-phenylene) 0,0,0,0-tetramethyl        phosphorodithioate,    -   Dimethoate: ((0,0-dimethyl S-(n-methylcarbamoylmethyl)        phosphorodithioate,    -   Formothion: S[2-formylmethylamino]-2-oxoethyl]-O,O-dimethyl        phosphorodithioate,    -   Phenthoate: 0,0-dimethyl        S-(alpha-ethoxycarbonylbenzyl)-phosphorodithioate.

In addition, especially for ticks and mites, the following insecticidesmay be applied:

-   -   neonicotioids as acetamidiprid and imidacloprid:        1-(6-chloro-3-pyridylmethyl)-N-nitro-2-imidazolidinimine;    -   pyridins as pyriproxyfen:        2-[1-+methyl-2-(4-phenoxyphenoxy)ethoxyy]pyridine;    -   pyrimidines as pyremidifen        5-chloro-N-(2,-[4-(2-ethoxyethyl)-2,3-dimethyl-phenoxy]-ethyl)6-ethylpyrimid        in-4-amin    -   quinazoliner as fenazaquin: 4-[[-(1,1-dimethylethyl)phenyl,        pyrazoler and phenyl    -   pyrazoles as dihydropyrazole, fipronile, tebufenpyrad, and        fenpyroproximate:        1,1-dimethylethyl-4-[[[[(1,3-dimethyl-5-phenoxy-1H-pyrazol-4-yl)-methylene]ammo]oxy]methyl]benzoate]    -   pyrazoner as tebufenpyrad,    -   carbonitrils as vaniliprol,    -   hydrazins as tebufenozide,    -   hydrazons,    -   azomethins,    -   diphenyls as bifenazate    -   benzoylurea and derivatives thereof.

Furthermore active insecticides with a sterilising effect on adultmosquitoes and/or with a growth regulating effect may applied such as:

-   -   (alfa-4-(chloro-alpha-cyclopropylbenzylidenamino-oxy)-p-tolyl)-3-(2,6-diflourobenzoyl)urea,    -   Diflubenzuron:        N-(((3,5-dichloro-4-(1,1,2,2-tetraflouroethoxy)phenylamino)        carbonyl)2,6 diflouro benzamid,    -   Triflumuron: 2-Chloro-N-(((4-(triflouromethoxy)        phenyl)-amino-)carbonyl) benzamide, or    -   a triazin such as N-cyclopropyl-1,3,5-triazine-2,4,6-triamin.

A fencing according to the invention implies a large variety ofapplications. Examples are a cattle field, an agricultural area, avillage, a refugee camp, a children playground, a sports ground,stadium, a swimming pool, a market place and any private or publicbuilding, such as a hospital or a school.

A fencing according to the invention may protect different kinds ofagricultural plants from insects. Table 3 below shows a number cropswhich may be subject to damage due to certain insects.

TABLE 3 Insect Common name Crop Helicoverpa (Heliothis) Americanboliworm, Cotton, Gram, Pigeon armigera fruit/pod borer, Pea, Tomato,Chilies, Tobacco etc. Spodoptera litura Tobacco caterpillar Cotton,Cauliflower, Cabbage, Green Gram, Black Gram, Chillies, Tobacco etc.Erlas vitella Spotted Bollworm Cotton, Lady finger Erlas insulana SpinyBoliworm Cotton, Lady finger Pectinophora gossypiella Pink BollwonnCotton Scirpophaga incertuias Yellow Stemborer Paddy (Rice)

DETAILED DESCRIPTION/PREFERRED EMBODIMENT

The invention will be explained in more detail in the following withreference to the drawings, where

FIG. 1 shows a fencing according to the invention in a perspective view,

FIG. 2 shows the fencing in a cross sectional view.

The preferred embodiment of the invention is, as shown in FIG. 1. Afencing 1 with a mesh structure 2 which is attached to rigid,substantially upright support members 3 to which the mesh 2, preferablya stiff net, is attached. The size of the openings in the mesh may bechosen to prevent certain insects to traverse the fencing 1, whilesmaller insects have the possibility to move through the mesh openings.The size of the openings in the mesh may alternatively be chosen toprevent almost any insect to traverse the mesh.

An insect 4, which is crawling on the ground surface 5 may pass thefencing, because the lower edge of the mesh is located at a certainheight above the ground.

Alternatively, for prevented crawling insects from entering the openarea, the fencing structure 2 may extend onto the ground surface 5 orinto the ground as shown in FIG. 2. As a safety arrangement, the groundpart 7 of the fencing structure may extend into the ground a certaindistance, for example 0.2 m, below the ground surface. This way, alsothose insects that traverse the top soil 8 under the ground surface 5are prevented from reaching the open area 6.

The mesh 2 as well as the ground part 7, which for example may be atarpaulin attached to the mesh 2, may be impregnated with aninsecticide, which is transferred to an insect that touches the mesh 2or the ground part 7. This reduces the number of insects around the openarea 6 that is desired free from nuisance insects.

If the mesh 2 does not comprise an insecticide, or in case a flyinginsect 11 is resistant to the insecticide, this insect 11 may afterhaving approached the mesh 2, which is indicated by trajectory 9, moveunaffected upwards along the surface of the mesh 2, which is indicatedwith trajectory 9′, in order to get around the obstacle. In this case,it is of advantage to provide the fencing structure with a top part 10′which is bent away from the open area 6 and preferably a top part 10which is bent downwards in order to trap these insects 11 which then,after a while, die due to exhaustion.

Preferably, this top part is impregnated with an insecticide to kill theinsect 11. It may alternatively be treated with or having attached to itan object or structure that release pheromones thus making the top partinto a trap for the species lured to the used chemical. This trap maywork with or without supplementary insecticides

In case that the mesh 2 is impregnated with a certain insecticide, theinsecticide for the top part 10 or 10′ is preferably different from theinsecticide which is used for the mesh 2. Thus, an insect 11 which maybe resistant to the insecticide of the mesh, for example a pyrethroid,would in this case be killed by the insecticide of the top part 10, forexample an organophosphate based insecticide. In areas with resistanceto both of these traditionally used insecticides, new insecticides canwith economic advantage be used with the fence, since the more limitedapplication of these often more expensive chemicals can make theseaffordable for more crops or other areas to be protected.

1. A fencing for preventing low-flying insects from entering an open airarea comprising a substantially upright structure at least partlysurrounding said area, said structure having a height suitable forpreventing the low-flying insects from entering said open-air area,wherein at least part of said structure is provided with an insecticidetransferable to said low flying insects touching said at least part ofsaid structure, wherein said insecticide is provided within said atleast part of said structure by impregnating or incorporating saidinsecticide in a material of said at least part of said structure forgradual migration of said insecticide from an interior of said at leastpart of said structure through the material to surfaces of said at leastpart of said structure for long lasting insecticidal efficiency of saidat least part of said structure, wherein said insecticide is selectedfrom the group consisting of a pyrethroid based insecticide, anorganophosphorus based insecticide, a carbamate based insecticide, aninsecticide affecting ticks or mites, an insecticide with a sterilizingeffect or growth regulating effect on insects or acarides, andcombinations thereof.
 2. A fencing according to claim 1, wherein saidinsecticide further comprises pyrethroid compounds selected from thegroup consisting of: Ethofenprox:2-(4-ethoxyphenyl)-2-methylpropyl-3-phenoxybenzyl ether, Fenvalerate:(RS)-alpha-cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl)-3methylbutyrate, Esfenvalerate:(S)-alpha-cyano-3-phenoxybenzyl(S)-2-(4-chlorophenyl)-3-methylbutyrate,Fenpropathrin: (RS)-alpha-cyano-3-phenoxybenzyl2,2,3,3-tetramethylcyclopropanecarboxylate, Cypermethrin:(RS)-alpha-cyano-3-phenoxybenzyl (1RS)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,Permethrin: 3-phenoxybenzyl (1RS)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,Cyhalothrin:(RS)-alpha-cyano-3-phenoxybenzyl(Z)-(1RS)-cis-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate, Deltamethrin: (S)-alpha-cyano-3-phenoxybenzyl(1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate,Cycloprotbrin: (RS)-alpha-cyano-3-phenoxybenzyl(RS)-2,2-dichloro-1-(4-ethoxyphenyl)cyclopropanecarboxylate, Fluvalinate(alpha-cyano-3-phenoxybenzylN-(2-chloro-alpha,alpha,alpha-trifluoro-p-tolyl)-D-valinate),Bifenthrin:(2-methylbiphenyl-3-ylmethyl)0(Z)-(1RS)-cis-3-(2-chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethylcyclopropanecarboxylate,2-methyl-2-(4-bromodifluoromethoxyphenyl)propyl (3-phenoxybenzyl)ether,Tralomethrin: (S)-alpha-cyano-3-phenoxybenzyl(1R-cis)3((1′RS)(1′,2′,2′,2′-tetrabromoethyl))-2,2-dimethylcyclopropanecarboxylate,Silafluofen: 4-ethoxyphenyl(3-(4-fluoro-3-phenoxyphenyl)propyl}dimethylsilane, D-fenothrin:3-phenoxybenzyl (1R)-cis, trans)-chrysanthemate, Cyphenothrin:(RS)-alpha-cyano-3-phenoxybenzyl (1R-cis, trans)-chrysanthemate,D-resmethrin: 5-benzyl-3-furylmethyl (1R-cis, trans)-chrysanthemate,Acrinathrin: (S)-alpha-cyano-3-phenoxybenzyl(1R-cis(Z))-(2,2-dimethyl-3-(oxo-3-(1,1,1,3,3,3-hexafluoropropyloxy)propenyl(cyclopropanecarboxylate,Cyfluthrin: (RS)-alpha-cyano-4-fluoro-3-phenoxybenzyl3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate, Tefluthrin:2,3,5,6-tetrafluoro-4-methylbenzyl (1RS-cis(Z))-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate, Transfluthrin: 2,3,5,6-tetrafluorobenzyl(1R-trans)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate,Tetramethrin: 3,4,5,6-tetrahydrophthalimidomethyl (1RS)-cis,trans-chrysanthemate, Allethrin:(RS)-3-allyl-2-methyl-4-oxocyclopent-2-enyl (1RS)-cis,trans-chrysanthemate, Prallethrin:(S)-2-methyl-4-oxo-3-(2-propynyl)cyclopent-2-enyl (1R)-cis,trans-chrysanthemate, Empenthrin: (RS)-1-ethynyl-2-methyl-2-pentenyl(1R)-cis,trans-chrysanthemate, Imiprothrin:2,5-dioxo-3-(prop-2-ynyl)imidazolidin-1-ylmethyl (1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)-cyclopropanecarboxylate,D-flamethrin: 5-(2-propynyl)-furfuryl (1R)-cis, trans-chrysanthemate,and 5-(2-propynyl)furfuryl 2,2,3,3-tetramethylcyclopropanecarboxylate;deltamethrin, etofenprox, alfacypermethrin, lambdacyhalothrin,cyfluthrin, and combinations thereof.
 3. A fencing according to claim 1,wherein said insecticide further comprises carbamate compounds selectedfrom the group consisting of: Alanycarb:S-methyl-N[[N-methyl-N—[N-benzyl-N(2-ethoxy-carbonylethyl)aminothio]carbamoyl]thioacetimidate,Bendiocarb: 2,2-dimethyl-1,3-benzodioxol-4-yl-methylcarbamate), Carbaryl(1-naphthyl N-methylcarbamate, Isoprocarb: 2-(1-methylethyl)phenylmethylcarbamate, Carbosulfan: 2,3 dihydro-2,2-dimethyl-7-benzofuranyl[(dibutylamino)thio]methylcarbamate, Fenoxycarb:Ethyl[2-(4-phenoxyphenoxy)ethyl]carbamate, Indoxacarb:Methyl-7-chloro-2,3,4a,5-tetrahydro-2-[methoxycarbonyl(-4-trifluoromethoxyphenyl)]Propoxur: 2-isopropyloxyphenol methylcarbamate, Pirimicarb:2-dimethylamino-5,6-dimethyl-4-pyrimidinyl-dimethylcarbamate,Thidiocarb: DimethylN,N′(thiobis((methylimino)carbonoyloxy)bisethanimidiothioate), Methomyl:S-methyl N-((methylcarbamoyl)oxy)thioacetamidate, Ethiofencarb:2-((ethylthio)methyl)phenyl methylcarbamate, Fenothiocarb:S-(4-phenoxybutyl)-N,N-dimethyl thiocarbamate, Cartap:S,S′-(2-5-dimethylamino)trimethylene)bis(thiocarbamate)hydrochloride,Fenobucarb: 2-sec-butylphenylmethyl carbamate, 3,5-dimethylphenyl-methylcarbamate, Xylylcarb: 3,4-dimethylphenylmethylcarbamate, andcombinations thereof.
 4. A fencing according to claim 1, wherein saidinsecticide further comprises organophosphorous compounds selected fromthe group consisting of: Fenitrothion: O,O-dimethyl 0-(4-nitro-m-tolyl)phosphorothioate, Diazinon:O,O-diethyl-0-(2-isopropyl-6-methyl-4-pyrimidinyl) phosphorothioate,Pyridaphenthion: 0-(1,6-dihydro-6-oxo-1-phenylpyrazidin-3-yl)0,0-diethyl phosphorothioate, Pirimiphos-Etyl: 0,0-diethyl0-(2-(diethylamino) 6-methyl-pyrimidinyl) phosphorothioate,Pirimiphos-Methyl:0[2-(diethylamino)-6-methyl-4-pyrimidinyl]0,0-dimethyl phosphorothioate,Etrimphos:0-6-ethoxy-2-ethyl-pyrimidin-4-yl-0,0-dimethyl-phosphorothioate,Fenthion: 0,0-dimethyl-0[-3-methyl-4-(methylthio) phenylphosphorothioate, Phoxim:2-(diethoxyphosphinothoyloxyimino)-2-phenylacetonitrile, Chlorpyrifos:0,0-diethyl-O-(3,5,6-trichloro-2-pyrinyl) phosphorothioate,Chlorpyriphos-methyl: 0,0-dimethyl 0-(3,5,6-trichloro-2-pyridinyl)phosphorothioate, Cyanophos: 0,0-dimethyl 0-(4-cyanophenyl)phosphorothioate, Pyraclofos:(R,S)[4-chlorophenyl)-pyrazol-4-yl]-0-ethyl-S-n-propyl phosphorothioate,Acephate: 0,S-dimethyl acetylphosphoroamidothioate, Azamethiphos:S-(6-chloro-2,3-dihydro-oxo-1,3-oxazolo[4,5-b]pyridin-3-ylmethylphosphorothioate, Malathion: 0,0-dimethyl phosphorodithioate ester ofdiethyl mercaptosuccinate, Temephos: (0,0′(thiodi-4-1-phenylene)0,0,0,0-tetramethyl phosphorodithioate, Dimethoate: ((0,0-dimethylS-(n-methylcarbamoylmethyl) phosphorodithioate, Formothion:S[2-formylmethylamino]-2-oxoethyl]-O,O-dimethyl phosphorodithioate,Phenthoate: 0,0-dimethylS-(alpha-ethoxycarbonylbenzyl)-phosphorodithioate, and combinationsthereof.
 5. A fencing according to claim 1, wherein said insecticidefurther comprises insecticide affecting ticks or mites selected from thegroup consisting of: neonicotioids as acetamidiprid and imidacloprid:1-(6-chloro-3-pyridylmethyl)-N-nitro-2-imidazolidinimine; pyridins aspyriproxyfen: 2-[1-+methyl-2-(4-phenoxyphenoxy)ethoxyy]pyridine;pyrimidines as pyremidifen5-chloro-N-(2,-[4-(2-ethoxyethyl)-2,3-dimethyl-phenoxy]-ethyl)-6-ethylpyrimidin-4-amin quinazoliner as fenazaquin: 4-[[-(1,1-dimethylethyl)phenyl,pyrazoler and phenyl pyrazoles as dihydropyrazole, fipronile,tebufenpyrad, and fenpyroproximate: 1,1-dimethylethyl-4-[[[[(1,3-dimethyl-5-phenoxy-1H-pyrazol-4-yl)-methylene]ammo]oxy]methyl]benzoate]pyrazoner as tebufenpyrad, carbonitrils as vaniliprol, hydrazins astebufenozide, hydrazons, azomethins, diphenyls as bifenazate,benzoylurea and derivatives thereof, and combinations thereof.
 6. Afencing according to claim 1, wherein said insecticide with asterilizing or growth regulating effect further comprises insecticideaffecting ticks or mites selected from the group consisting of:(alfa-4-(chloro-alpha-cyclopropylbenzylidenamino-oxy)-p-tolyl)-3-(2,6-difluorobenzoyl)urea,Diflubenzuron:N-(((3,5-dichloro-4-(1,1,2,2-tetrafluoroethoxy)phenylamino) carbonyl)2,6difluoro benzamid, Triflumuron:2-Chloro-N-(((4-(trifluoromethoxy)phenyl)-amino-)carbonyl)benzamide, atriazin such as N-cyclopropyl-1,3,5-triazine-2,4,6-triamin, andcombinations thereof.
 7. A fencing for preventing low-flying insectsfrom entering an open air area comprising a substantially uprightstructure at least partly surrounding said area, said structure having aheight suitable for preventing the low-flying insects from entering saidopen-air area, wherein at least part of said structure is provided withan insecticide transferable to said low flying insects touching said atleast part of said structure, wherein said insecticide is providedwithin said at least part of said structure by impregnating orincorporating said insecticide in a material of said at least part ofsaid structure for gradual migration of said insecticide from aninterior of said at least part of said structure through the material tosurfaces of said at least part of said structure for long lastinginsecticidal efficiency of said at least part of said structure, whereinsaid structure is a net made of polymer fibers with the insecticideincorporated in said polymer fibers for the gradual migration of saidinsecticide from interiors of said fibers to surfaces of said fibers forthe long lasting insecticidal efficiency of said structure.
 8. A fencingfor preventing low-flying insects from entering an open air areacomprising a substantially upright structure at least partly surroundingsaid area, said structure having a height suitable for preventing thelow-flying insects from entering said open-air area, wherein at leastpart of said structure is provided with an insecticide transferable tosaid low flying insects touching said at least part of said structure,wherein said insecticide is provided within said at least part of saidstructure by impregnating or incorporating said insecticide in amaterial of said at least part of said structure for gradual migrationof said insecticide from an interior of said at least part of saidstructure through the material to surfaces of said at least part of saidstructure for long lasting insecticidal efficiency of said at least partof said structure, wherein said structure is a net made of polymerfibers impregnated with the insecticide for gradual migration of saidinsecticide from the interior of said fibers to surfaces of said fibersfor the long lasting insecticidal efficiency of said structure.
 9. Afencing according to claim 7, 8 or 1, wherein said structure issupported on solid ground and wherein said structure comprises a groundpart extending into the ground for preventing ground crawling insectsand top soil traversing insects from entering said area.
 10. A fencingfor preventing low-flying insects from entering an open air areacomprising a substantially upright structure at least partly surroundingsaid area, said structure having a height suitable for preventing thelow-flying insects from entering said open-air area, wherein at leastpart of said structure is provided with an insecticide transferable tosaid low flying insects touching said at least part of said structure,wherein said insecticide is provided within said at least part of saidstructure by impregnating or incorporating said insecticide in amaterial of said at least part of said structure for gradual migrationof said insecticide from an interior of said at least part of saidstructure through the material to surfaces of said at least part of saidstructure for long lasting insecticidal efficiency of said at least partof said structure, wherein said structure has a lower edge positionedbetween about 5 cm and about 20 cm above ground, for allowing crawlinginsects to pass said structure.
 11. A fencing according to claim 10, 7,8 or 1, wherein said structure comprises a top part which is bent into aconcave structure for trapping insects, the top part further comprisinginsecticide on the top part transferable to insects touching said toppart.
 12. A fencing according to claim 11, wherein the top part furthercomprises insect attractants selected from a group consisting of insectattracting agents, pheromones, insect luring agents, and combinationsthereof.
 13. A fencing according to claim 11, wherein the insecticidetransferable from the top part is different from the insecticideprovided within said at least part of the structure.
 14. A fencingaccording to claim 10, 7, 8 or 1, further comprising rigid,substantially upright frame members, on which said structure isattached.
 15. A fencing according to claim 10, 7, 8 or 1, wherein saidstructure for preventing said low flying insects from entering said areacomprises at least one structure selected from the group consisting of arigid wall, a foil, a fabric, a perforated foil, a perforated laminate,and a mesh with openings of a size smaller than said insects, andcombinations thereof.
 16. A fencing according to claim 10, 7, 8 or 1,wherein said structure further comprises UV protective and UV resistantmaterial to prevent decomposition of said insecticide.
 17. A fencingaccording to claim 10, 7, 8 or 1, wherein said structure furthercomprises UV protective and UV resistant material for preventingdecomposing of said structure due to UV radiation.
 18. A fencingaccording to claim 10, 7, 8 or 1, wherein said structure furthercomprises insect attractants selected from the group consisting ofinsect attracting agents, insect lures, pheromones, pheromone mimics,and combinations thereof.
 19. A fencing according to claim 10, 7, 8 or1, wherein said structure has a color for attracting certainpre-selected insect pests.
 20. A fencing according to claim 10, 7, 8 or1, wherein said structure is black for being invisible for certaininsects.
 21. A fencing according to claim 10, 7, 8 or 1, wherein theheight of the structure is between about 0.5 m and about 2 m.